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Weather Station Hardware => Davis Instruments Weather Stations => Topic started by: captgadget on July 07, 2020, 10:57:06 AM

Title: Wrong wind direction
Post by: captgadget on July 07, 2020, 10:57:06 AM
All of a sudden my wind vane is off 90°. I took it off the mount, put on the workbench, and aligned the way the manual tells and I'm still off 90°. The one thing I noticed on the bench with the vane removed my the flat spot of my shaft doesn't come true to the right. It's off a few degrees. Would that make any difference?
Title: Re: Wrong wind direction
Post by: SnowHiker on July 07, 2020, 08:58:24 PM
All of a sudden my wind vane is off 90°. I took it off the mount, put on the workbench, and aligned the way the manual tells and I'm still off 90°. The one thing I noticed on the bench with the vane removed my the flat spot of my shaft doesn't come true to the right. It's off a few degrees. Would that make any difference?
Assuming the 90° difference is constant, you can check the console and make sure an offset wasn't somehow added accidentally, and if it wasn't, then you can add an offset to correct the reading.

As long as you followed the manual when you had the anemometer down, I'm not sure what else you can check for.  I think it's possible the shaft could have gotten off, but if it's reading 90° off, then it seems to me the shaft would also have to be 90° off and not just a few degrees, but I guess maybe it could be a symptom of something else being loose.

In any case I think I would adjust the offset and see if it sticks.

If you have a clear night, you can also look for Polaris, the North Star.  If it's 90° off and in the east or the west, you have a whole 'nother problem.  :lol:
Title: Re: Wrong wind direction
Post by: galfert on July 07, 2020, 09:08:08 PM
If you are having trouble locating Polaris (some people have obstructed views because of trees) then you can use a compass. If you are using a magnetic compass be sure to find out what the current magnetic declination is for your location so that you can find True North. The magnetic North Pole has been moving rather quickly in recent years and nobody knows why so it is important to have current declination information.

https://www.magnetic-declination.com/

Another way is with a mobile app that has a True North compass. If you have Android the following is my favorite:
https://play.google.com/store/apps/details?id=com.eclipsim.gpsstatus2
Title: Re: Wrong wind direction
Post by: SnowHiker on July 07, 2020, 09:25:39 PM
The one thing I noticed on the bench with the vane removed my the flat spot of my shaft doesn't come true to the right. It's off a few degrees. Would that make any difference?
Just to check, I hooked up my spare newer model anemometer and checked the shaft orientation, the flat side does indeed point to the right (east if it was mounted facing north) when the console is showing north, so that seems to help verify that's not your whole problem.

Sorry I got off on Polaris, I'm sure that's not your problem.  Unless the anemometer mount spun around on the pole, but surely you would have noticed that when you took it down.
Title: Re: Wrong wind direction
Post by: SnowHiker on July 11, 2020, 01:43:17 AM
Did you get it figured out?
Title: Re: Wrong wind direction
Post by: captgadget on July 11, 2020, 09:13:16 AM
No, I think I will email Davis and see what they tell me. Thank you
Title: Re: Wrong wind direction
Post by: captgadget on July 11, 2020, 09:16:00 AM
If you are having trouble locating Polaris (some people have obstructed views because of trees) then you can use a compass. If you are using a magnetic compass be sure to find out what the current magnetic declination is for your location so that you can find True North. The magnetic North Pole has been moving rather quickly in recent years and nobody knows why so it is important to have current declination information.

https://www.magnetic-declination.com/

Another way is with a mobile app that has a True North compass. If you have Android the following is my favorite:
https://play.google.com/store/apps/details?id=com.eclipsim.gpsstatus2

Love that android app
Title: Re: Wrong wind direction
Post by: SnowHiker on July 11, 2020, 03:25:14 PM
There's not a whole lot that it could be.  Either the anemometer or the console.  Did you check the offset, or try adjusting the offset?
Title: Re: Wrong wind direction
Post by: captgadget on July 11, 2020, 05:04:55 PM
In weatherlink live under configuration in advanced options, there is a setting for the direction of the vane. I typed in there 130° because that is the direction it is pointing when it shows SW on my app.